Is there a quick explanation of what signal actually does? I don't understand the need for a phone number either. Jami doesn't ask for a phone number. It has other deficiencies that make me not want to use it, but those are technical rather than policy, more or less. Similarly, irc (I'm luddite enough to still be using it) doesn't ask for a phone number either. So this is all suspicious. There are a bunch of other things like this too (Element, Matrix, etc.) that I haven't looked into and tbh I don't understand why they exist.

Because it's centralized, I prefer SimpleX.

They implemented an alt method IIRC but you must go out of your way to search and find it. I just recall seeing a bunch of post headlines about using email or something like that a year or so back.

They send an initial SMS message that is a main expense and funded by some rich person and donations. I think that has some significance to encryption or something but I'm not sure of the details. I could be wrong on that one, it has been years since I read the details.

Jami.net

Ignore the comment saying signal is "end to end encrypted" "private" etc They are simply stuck in a delusional state where they try to convince themselves that signal is the best option so they can continue using it. Nothing is private if it isn't fully libre because you never know what the proprietary code is doing. The signal protocol itself has its source code released, and the encryption and security code is publicly available, but the signal Foundation has stated that it uses both free code and proprietary code. Their reason is UI, but it's hard to make sure whatever proprietary code is being used for because you simply can't see it. As GNU puts it: "You're walking in a pitch black cave". Jami is fully libre and is a GNU project. You don't even need any phone number!

thousands of threads on this topic since decades ago.

it's an eternal debate (since signal has no plans to change)

just read the history and join the rest of us waiting for them to change. using signal before that change is completely optional. go ahead and don't use it. no problem.

opening the discussion again is just tiring.

Session is what you want. But you have to directly shares each others public keys to connect